The present invention is related to optical heads and their manufacture in wafer form.
A schematic of an embodiment of an optical head is shown in FIG. 2. The head comprises a number of discrete parts: a slider body, a movable micro-machined tracking mirror, a fiber, a magnetic writing coil, a molded glass lens, a lens holder, and possibly a quarter-wave plate. The quarter wave-plate plate may be needed when a polarization-maintaining fiber is used, but is not used when a low-birefringence fiber is used. Assembly of this head is complex due to the small size of the components and to tight alignment tolerances. The lens-to-slider and coil-attach processes are particularly time-consuming and tedious. Another disadvantage is that the lenses are molded one piece at a time, leading to high costs and difficulty in handling. Furthermore, the lens is limited to a numerical aperture (NA) less than 0.85, resulting in a maximum areal density of around 4 Gb/in2 using a 660 nm laser, quad-MO media, and a conventional read channel.
What is needed is a head design that makes head assembly more efficient and that offers a path to significantly higher areal densities.
The present invention includes an optical head for transferring a light from a source to a storage disk of a storage drive, comprising: a first block; a reflective element, the reflective element coupled to the first block to direct the light to the disk; a second block, the second block coupled to the first block; and a first lens, the first lens for focusing the light onto the disk; and the first lens formed of the second block. The first and/or second blocks may comprise GaP (Gallium Phosphorus). The second lens may comprise a near-field lens. The first block may comprise silicon. The second block may comprise GaP. The optical head may also comprise a third block, the third block disposed between the first and second blocks and coupled thereto. The optical head may also comprise as second lens, wherein the second lens is formed of the third block. The third block may comprise GaP. The first lens and the second lens may provide an NA of at least 1.13.
The present invention also includes a storage system comprising: a source, the source providing a light; a storage disk; a head; a first block; a reflective element, the reflective element coupled to the first block to direct the light to the storage disk; a second block, the second block coupled to the first block; and a first lens, the first lens formed of the second block, and the first lens for focusing the light onto the storage disk. The second block may comprise GaP. The first lens may comprise a near-field lens. The first and/or second blocks may comprise GaP. The first block may comprise silicon. The optical head may also comprise a third block, the third block disposed between the first and second blocks and coupled thereto. The optical head may further comprise a second lens, wherein the second lens is formed of the third block.
The present invention may also comprise a disk drive head, including: a light directing means for directing a light towards a storage medium; and a focusing means for focusing the light onto the storage means, wherein the light directing means is coupled to the focusing means.